In an OFDM scheme, i.e., an orthogonal frequency division multiplexing scheme, a transmission apparatus allocates different pieces of data to multiple subcarriers that are orthogonal carriers to transmit data. The subcarriers used in an OFDM scheme are narrowband. Thus, an occurrence of frequency-selective fading may cause a transmission error in data allocated to a subcarrier having a low reception electric field intensity, but it does not cause a transmission error in data allocated to a subcarrier having a high reception electric field intensity. Non-Patent Literature 1 discloses a technology for improving transmission quality by application of interleaving and an error correction code in a transmission apparatus to correct a transmission error caused by frequency-selective fading.